Or what about problem solved button. After getting your answer we can press the it so the answer come to the top and highlight 

@karter

Not a bad idea, +1 for you 

waiting for more replies especially admins 

Thank you for the suggestion. We will take considering to give additional features like this credit/reputation giving away or getting  in future forum updates.

Actually we can give "Like" for individual post. Based on the help/information received we can endorse by giving like at the moment. 

There's already a like button with every posts. We can hit that 

I think he is talking about some rewards/points after receving the like +1 for this